


Fatass Tankery Exercise

by Gothdresser



Category: Girls und Panzer
Genre: Diaper, F/F, Fatty - Freeform, Panty Poop, Pantypoop, Pee, Piss, Scat, Soiling, Trapped in a tank, Weight Gain, messing, multiple messes, panty soiling, poop, pull-up, underwear soiling
Language: English
Status: Completed
Published: 2019-06-22
Updated: 2019-06-22
Packaged: 2020-05-16 18:13:17
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,475
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19323448
Author URL: https://archiveofourown.org/users/Gothdresser/pseuds/Gothdresser
Summary: Messy fun in a tank with Team Anglerfish of GuP's Ooarai Girls Academy, although one girl is just a tiny bit bigger after a fun summer break~





	Fatass Tankery Exercise

Lumbering her enlarged ass over to her Panzer IV, Miho struggled with the buttons on her tankery uniform due to her new size. Summer vacation had been quite an interesting one for her since she went back home for it. She had gone in trying to indulge her silly, messy fetish, and in return, she had developed a new one. Maho really did want to pamper her, both with sweets and diapers, and the effect was an insatiable sweet-tooth and becoming nearly incontinent. However, with her new, bigger shape, Miho wanted to keep some of her pride, and that meant no more diapers when she was out in public. It wasn't like she couldn't hold it, but she did have problems telling sometimes when she wasn't wearing her padding, often confusing wetting herself for sweat or crapping herself for some uncomfortable position of her fat ass. Miho was still a big girl though, in terms of size and hopefully confidence, and she didn't want a diaper bulging out below her skirt. Worse yet, the skirt was covering even less than it did before, a fall breeze lapping at her butt as the second semester of the school had started. The Public Morals Committee already grilled her this morning about the ill-fitting uniform, only letting her go as they couldn’t find a uniform bigger than the XXL one she was already wearing.  


Hopefully too many wouldn’t notice the big difference, but as Miho finally approached her squad, she didn’t even get a greeting out before a certain ginger-haired girl started off on her. “Oh jeez, what were you doing this summer to get so heavy, Miho? I was devastated at the possibility of you having found a boyfriend, but I can see that wasn’t the case.” Saori was looking Miho’s body up and down, and up and down again to make sure she got all of her large size.  


“Now now, Saori, Miho looks just fine.” The most level-headed of the group, Hana was there to calm the situation down, but even she looked somewhat unsure at how big their commander was now. “It’s not like tankery is too physical of a sport. As long as she can give commands, it should hopefully be fine…” Taking a gulp as she looked Miho’s new size up and down herself, she repeated her, “...hopefully…” again under her breath.  


With a blush on her face, Miho rubbed her slabs of fat she called thighs together as she tried to think of something to say in response, looking towards Mako or Yukari for some support, but all she got was light snoring and a shrug, respectively. “I’ll definitely be fine, it’s only a little weight, and it won’t affect my abilities as a commander. Now, let’s get ready for practice already.”  


Swinging both her large arms to motion them into the tank, Miho shook Mako awake and followed them, letting them in first. Just climbing the tank was quite the struggle and Miho almost considered giving up and asking for some help, but she had to prove Saori wrong by pulling herself up onto Panzer IV. She somehow managed to get her chunky thighs over into the cupola as well but her size getting the best of her as she found herself stuck with her lower half only inside the tank. It wasn’t the best scenario, but neither was it as bad as one might expect since she was practically in the same position as usual. She just wasn’t able to see into the tank, but Alice had shown her the foot thing, so maybe that could work here as Miho’s legs dangled in the tank.  


Although tight, resting here halfway in the tank wasn’t as bad as she expected. There was a little pinch here and there, but as she adjusted herself, Miho did find a pretty comfortable spot that she could take a load off in. Maybe a little too literally as she felt a little more than a fart come out, and Miho started the practice with her regular, “Panzer vor!” along with a light blush on her face. Miho hoped that would be all that’d be coming out of her for the rest of practice, but it wouldn’t be too long to endure holding more.  


The same couldn’t be said for inside the tank though as Mako’s handling got the tank rumbling forward, crunching concrete and dirt beneath it as the practice started. It was just a simple splitting up into sub-teams for dodge training, but the effect could be felt by everyone, the slap of Miho’s legs jiggling against each other echoing in the tank. Such sounds helped only a little to keep Mako awake though as morning practice meant she didn’t get to sleep in as much and she found herself yawning more than usual, her skills slipping a little as she tried to open her eyes past the morning crustiness. Rubbing an eye with one hand while not keeping her full attention on the trail, the tank got jostled around quite a bit by hitting a rock Mako didn’t do very well in avoiding. She ignored the complaints coming from the back of the tank after it until a particularly rank smell came flooding into the tank and Mako found her sleepy head getting heavier.  


Up above, Miho’s lower body was out of her sight and a bit out of her control, her legs hitting together, hitting the tank, and hitting something softer, but she couldn’t hear any complaints from inside the tank. One particular jump of the tank surprised her though, and Miho found herself grabbing what parts of the hatch weren’t covered by her fattiness to steady herself. She couldn’t steady her bowels though as she found her ass unable to hold a second wave of messiness that spread her cheeks of fat apart again to load up her panties quite a bit more. The tank even seemed less stable than before as Miho could feel the heavy smacking of her sagging poopy panties against the back of her calves, past her knees already after only two messes. Breakfast was always the most important meal of the day, but maybe she went a little too hard on it with the extra few cinnamon buns. Ventilation was decent depending on what tank it was, but with how some of these tanks were repaired and restored, Miho didn’t know if an air pump would be needed here, even if she did know how bad her soiled undies could be.  


Smell didn’t matter much though as a shot from behind rocked the tank and Miho struggled to look behind her, her fattiness inhibiting turning around. Lifting herself up as much as her fatty strength would let her, Miho found herself a little stuck as she tried to turn herself around, forcing it all that she could. It was a little too much though as she finally loosened herself unexpectedly, whipping her body around a little too fast and her sagging panties slapped lightly against the back of her thighs until it rested back against them. She finally had eyes now on the enemy tank with her new position, radioing it in to Saori. “Rabbit coming up from behind. Most shots starboard. Hide in the forest ahead.” She did have to wait a few moments though for her commands to take effect as she could barely turn around enough again to see that a tree was coming up and the tank was coming dangerously near it. Closing her eyes, Miho waited the few seconds for the upcoming branch, feeling her thighs grow warm and wet before being tossed to the side a bit on the sudden turn of the tank. Rushing past them came the Rabbit team though with no other teams in sight for the time being. “All clear, how’s everyone doing in the tank?” Again, Miho waited for a response, although even trying once more was met with a lack of a response, so Miho just turned out once more to face forward, waiting for some communication back.  


Hand over her mouth as the tank was rocking back and forth, Hana did her best to steady the tank as she could hear shots coming on the right side. One shot did hit unexpectedly, although it was a sagging pair of panties rather than a shell that hit her in the head. Her head was knocked against the gun and Hana was seeing double for a few moments as she steadied herself. She even saw double of the passed-out Mako, her jumbled head scrambling to push her body over to the driver seat. Fighting against the movement of the tank as she moved towards the driver’s seat to steady the tank, a few splashes and a solid dripping were coming from somewhere nearby and she feared that a leak was happening, but Mako’s unconscious body was making driving troublesome. “Yukari, please pull Mako out, I have to take over for driving!” Good for her that Yukari was quite obedient, although she got a whiff of the bad smell in the tank worsening as she focused on getting the tank in control, steadying it out while narrowly avoiding tree in front of them.  


It was almost right into another tree though as Hana’s body started going off by itself, her eyes widening as her legs began to shake and her vision lifted slightly. The sounds of crapping echoed through the tank again to shortly overpower the annoying dripping. Only the last minute jerk of her arms to the side in panic saved them from full-on crashing the tank, and Hana slowed the tank down as she tried to slow her breathing. Once she had calmed down though, Hana noticed the wetness beneath her and she had to feel her own crotch to confirm its dryness, meaning that… With a quick look towards Miho and another towards the path that Yukari dragged Mako out of the seat, Hana wasn’t too surprised by the smell of piss accompanying the shit and the puddles from below both Mako and Miho. Yukari didn’t smell the best either, although she couldn’t tell if that was because of her or Miho again, leaving Saori as the last one left clean there.  


However, Hana didn’t even need to look over to Saori to see what she was doing, the ginger-haired girl yelling on the radio to the other teams for back-up while trying to yell at Miho as well. The only response Saori got for all her hollering was another dose of the disgusting smell, but now she could see what was causing it. With the tank’s steering in Hana’s control now, Miho’s fat thighs stopped wobbling enough for her to see the panties drooping far below her skirt, almost past her feet even after… that couldn’t be the work of a single mess with how terrible the smell in the tank was, enough that she had to even crack open the side vents to air as much as she could out. It wasn’t too effective though as the smell of however many times Miho shit her panties like an overgrown infant was getting to her head, not to mention trying to radio to other teams for back-up, only to be met with their laughter. What was so funny about being in a tank with a fat ass crapping herself over and over again?!  


Anger wasn’t a good thing for her complexion though, and neither was it for her panties. Her voice wasn’t the only thing Saori was straining as she sat up and yelled again at the Rabbit team for giggling every time she said ‘poop’ or gasping when she swore. Instead of a blood vessel popping, something plopped into her panties as she stopped mid-shouting and her eyes widened. It was too little too late as Saori’s hands balled into fists and she wanted to lash out, but a scary realization slipped out of her mouth. “No boy is going to want a girl that shits her panties…” Not even caring anymore about the actual mess in her panties, Saori sat back down and squished the mess under her big butt. She could even feel it smush between the crack and towards her crotch, but it didn’t seem like it mattered much in her disheartened state. “A boy would probably even take a fat ass like Miho than my crappy ass…”  


It was too low for Hana to hear what Saori was saying quietly to herself after she stopped randomly in the middle of her ranting, although the even heavier and disgusting smell in the air gave her a hint. It seemed like no one but her and Yukari was in the right mind currently, although something about Yukari made her a bit suspicious. “How’s Mako doing, Yukari? And what about yourself? I hope you haven’t succumbed to the fate of our teammates as well.”  


“Ehehe, about that... I may have had a not-so-little misunderstanding~” Yukari just giggled to herself as she wiggled her butt down where she was sitting in the tank. She hadn’t thought there would ever be the chance to do this no matter how interested in it she was, but finally, she managed to mix her fetish and passion together. The situation being so impromptu was much more exciting than she imagined as she lifted her butt to give her messy butt a squeeze. “I, uh… I thought Commander Miho was having us do an exercise. No bathroom in tanks after all, but I don’t think we’re doing too well, heh~” Their commander’s panties were sagging past her legs at this point, Saori had gotten angry enough to poop herself, Yukari herself was indulging, she had heard something come from Hana just before, and Mako… “Oh, hey! I think Mako is waking up.”  


Groggily opening her eyes, Mako’s usual unhappiness at being awoken was worsened at getting a smell of all the crap happening inside the tank. “Ewwwww…” Sitting up while groaning though, she looked around a little at the various states of everyone else, unamused by what she missed. Worse yet, a hand of hers went down to check her crotch, coming back wet with a sigh. “Ugh, not again…” Giving one more look around the tank, Mako just shrugged her shoulders and went back to lying down. “Wake me up when the practice is over…”  


“I guess I’ll keep driving then, but we’re going back to the garages. Saori, can you…” Just one look towards the broken girl reminded her of that situation, even if she couldn’t make out the mumbling too much anymore. Her thoughts drifted to Yukari and Hana had figured her gut feeling and nose to be right earlier when Yukari had been right beside her to pull Mako out of the driver seat. There was a feeling of disappointment upon learning all their statuses, but now was not the time to be disgusted. Rather she turned the tank around and headed back through the forest towards the garage, taking over control of such a problematic situation. “Just get Miho’s attention or something since Saori is out of it and I don’t think Miho knows what’s going on.” A simple command and Yukari went right to slapping Miho’s closer thigh with one hand, even pinching it a little to make sure she’d respond finally, all while copping a feel of the messy panties that she was afraid would be gone soon.  


Her legs had felt a bit numb as Miho tried to kick them around a little as she waited while the tank drove forward, but after a while, it turned around and she eventually saw the tank garage coming into view. That already confused her as the practice was still going on, but suddenly she could barely feeling something pinching her leg within the tank and Miho grew afraid of some health issue. Lifting up with all her might, Miho loosened herself out of the cupola, feeling the red marks and indentations on her skin exposed to the fresh air. She’d definitely need some lotion on them after this if she could reach the spots, but as she climbed forward onto the Panzer IV, she had one hand pulling her forward while the other pulled up her drastically sagging panties, her ass cheeks partly on display. Maybe some exercise would have been better for her than some cake, but the thought of cake was so mouthwatering that Miho found herself distracted and drooling before resuming her work.  


It did feel like there was a bit of help on the other side though as the mess was finally pulled all the way out of the tank, Miho pulling her panties over to reveal Yukari’s smiling face and a salute on the other end. “Hello, Commander! Do you need a change?”  


“M-maybe just a little, but is everything alright in there?” Turning herself and her soiled undies around, Miho had trouble maneuvering around her large stomach to look in, but finally, she found a good angle by leaning over her fattiness. The state of the inner tank was quite the shitshow as Miho got a whiff and look at all that happened. Just one look at Hana’s expression and another back at her own panties were easy to connect, and Miho took a moment to respond to Hana’s expectant look. “Uuuh… O-oopsie, hehe…?”

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

“E-e-ehhhh?” Rubbing her thighs together as Miho had come to practice more than ready to lead again, here she was with a thick diaper being waved in front of her face, the rest of the package hanging from Hana’s other hand. “Wh-why do I have to wear a diaper? They’re embarrassing… Even if they are pretty soft…” She was almost tempted to just go along with it knowing how cold and uncomfortable tanks could be, but there was a reason she didn’t want to wear one yesterday. Her skirt already showed off her butt a fair bit and Midoriko had grilled her again today about it, but ultimately she was let go.  


“Oh, you know diapers are soft? I wonder if you had to wear them with how easily you seem to soil yourself.” Hana didn’t seem to be taking very much backtalk now as she pushed the diaper against Miho’s tummy. “Unless you get potty-trained and lose that stomach, you’re not allowed in the tank without a diaper.”  


“B-but I… You can’t do this.” Even when she was supposed to be the one leading them, those messy panties from yesterday were easily coming to bite her in the butt, and she could even feel the sting now. “I’m your c-command-uuugh… hrrrngh-er…”  


Dropping the pack of diapers, Hana’s hand went right to her nose. “See, you can’t even get into the tank before ruining your panties! Go change now or else we’ll only be a 4-person tank until you do. Now everyone in, and you can make your choice, Miho.”  


“Eh, uh, bu-...” Miho couldn’t even see her own butt to check out how bad the mess was, but she could already feel it sagging against her thighs, although she couldn’t tell if that wetness was a bladder leakage from crapping herself or… if her mess wasn’t too solid. She was feeling pretty cornered here and looking around, Mako and Yukari were already climbing into the tank. At least Saori was just getting onto it when Miho knew right away who her target could be. “Why do I have to wear a diaper if Saori soiled herself as well?” Hana didn’t seem to be pushing it onto her and Saori wasn’t even the commander either.  


The speed of which she heard her name was suspiciously fast though as Saori didn’t waste a moment “Oh, I don’t need diapers when I have… this!” Posing on top of the tank with her legs apart and lifting her skirt up, her bright pink underwear with princesses on the front was on full display and yet Miho recognized it as something thicker than just panties. “I had a problem keeping my temper down yesterday, but if I’m going to be a pottypants, I might as well be a super cute pottypants~” Turning around and swishing her butt to show glimpses of the backside, the thickness around her butt looking like she had more than a few overlapped pull-ups on, showing off parts of the various designs. Finally, Saori left with, “I even heard boys like girls with bigger butts~” before following Mako and Yukari into the tank.  


“W-well, a pull-up doesn’t count as a diaper… right?”  


“Please just put the diaper on, Commander. I’ll even change you into it if you like.”  


“O-okay, Hana. Did you make sure to get XXL diapers at least? Preferably XXXL.”  


“There are diaper sizes bigger than large?...”


End file.
